Glossary

The terms the docs and the API use, each defined once with the field or endpoint it appears in. The 3 terms people mix up most: a team owns the API keys and the billing, a profile groups accounts (one per brand, or one per customer when you build a platform), and an account is one connected platform login inside a profile.

10DLC

US carrier registration required before a US number can send SMS: a one-time brand registration plus a monthly campaign fee. One approved registration covers all your numbers. Other countries need no registration.

Account (connected account)

A platform login (an Instagram account, a Facebook Page, an X account) that a user authorized through the connect flow. Every account lives in exactly one profile, and every post, analytics and inbox call names it by its accountId.

Account-day

The billing meter for connected accounts: one unit per account per day it stays connected. At month end Zernio sums the account-days, divides by 30, and runs the result through the graduated price ladder. See Billing.

accountId

The _id of a connected account, returned by GET /v1/accounts. Most events carry it to say which account the event belongs to. To tell which customer an event belongs to, read externalId instead. Compare profileId.

API key

The credential every request sends as Authorization: Bearer $ZERNIO_API_KEY, created on the API keys page. One key covers a whole integration: rate limits scale with your connected accounts, not with your key count. See also scoped API key.

Branded Calling

Your business name, logo and reason for calling on the callee's phone, on calls from a US number attached to a verified caller identity. Priced per identity per month plus per branded call (Branded Calling).

Broadcast

A bulk message sent to a list of contacts on any inbox platform, created with POST /v1/broadcasts and delivered with POST /v1/broadcasts/{broadcastId}/send or queued with /schedule. WhatsApp broadcasts send an approved template, every other platform a plain message (with MMS attachments on SMS, and an optional messageTag on Instagram and Facebook to reach people outside the 24-hour window), and each recipient counts as one metered message.

Caller identity

The vetted record behind Branded Calling: display name, logo, call reasons, an authorizer and three references, created with POST /v1/branded-calling/identities and attached to numbers once verified. The carriers call it a Display Identity Record.

Connect flow

The OAuth handshake that turns a user's platform login into a connected account: GET /v1/connect/{platform}?profileId= returns an authUrl, the user approves there, and the account lands in that profile. The connecting accounts guide walks through it.

Contact

One person's identity across platforms, linked to the platform channels that reach them (phone number, Instagram-scoped id and the rest), listed by GET /v1/contacts and addressed by contactId. Zernio creates a contact when a message arrives, or you create one with POST /v1/contacts.

Content-hash dedup

The second layer of duplicate-post protection: the same (platform, accountId, content + media) fingerprint within 24 hours is rejected with 409 and the existingPostId. See Idempotency.

Conversation

One inbox thread of messages between an account and a person, listed by GET /v1/inbox/conversations and addressed by conversationId. Reply with POST /v1/inbox/conversations/{conversationId}/messages.

Direct message (DM)

A message sent to the account inside a conversation on Instagram, Facebook, WhatsApp or X. The inbox reads and answers them through the Messages endpoints; comments and reviews are separate resources.

Event

What Zernio sends to a webhook endpoint when something happens: post.published, message.received, account.connected and the rest of the event list. Delivery is at-least-once, so dedupe on the event id.

External post

A post published on the platform itself (in the Instagram app, for example) rather than through the API. A background sync picks external posts up roughly every 90 minutes per account; POST /v1/posts/sync-external fetches one on demand.

externalId

Your own identifier for a profile, typically the id of the customer or tenant it serves in your system, set on POST /v1/profiles or PUT /v1/profiles/{profileId}. It is unique among the profiles you own, GET /v1/profiles?externalId= finds the profile by it, and every event that belongs to a profile carries it back in profiles[]. See Build a platform.

Google Business Profile

The platform with value googlebusiness. Posts appear in Google Search and Maps, and the account is a location picked after OAuth; see the platform page.

Headless mode

A connect-flow variant (headless=true) where you build the Page, organization or board selection screen yourself instead of using the screen Zernio hosts, so nothing Zernio-branded is shown. See standard vs headless.

Idempotency key

A client-generated unique value that makes a retry safe. On POST /v1/posts it is the Idempotency-Key header: the same value within 24 hours returns the original post (200 with post) instead of a second post. The x-request-id header gives a narrower protection there (same value and same content). Profiles, SMS, inbox replies and ads take an Idempotency-Key header too. See Idempotency.

KYC

One-time identity verification required before provisioning phone numbers in regulated countries; review takes 1 to 3 business days. Unregulated countries provision instantly. See number availability.

Managed ad

The billing meter for ads: one unit per ad that is running or in review, counted daily across every connected ad account. Paused, ended and rejected ads leave the meter, and the first 500 are free; see Ads pricing.

MCP server

Zernio's Model Context Protocol server at mcp.zernio.com. It lets AI agents (Claude, Cursor, ChatGPT) call the API directly: post, read analytics, manage the inbox. See MCP setup.

Platform

One of the 16 platforms the API publishes to (Instagram, TikTok, X, LinkedIn and the rest), named by the platform value on each platforms[] entry. Each has its own capabilities and fields; see Platforms.

Post

Content created with POST /v1/posts, targeting one or more accounts through its platforms array. You create it as a draft, schedule it with scheduledFor, or publish it now with publishNow: true; it then moves through the statuses draft, scheduled, publishing and published, partial or failed. See the post lifecycle.

Presigned upload

The media upload flow: POST /v1/media/presign returns an uploadUrl to PUT the file to and a publicUrl to reference in posts. Uploads sit in temporary storage for 7 days. Creating or updating a post that uses them copies them to permanent storage.

Profile

A group of accounts inside your team, created with POST /v1/profiles: one per brand, or one per customer when you build for other people (the docs call that setup multi-tenant). Every new team starts with a "Default" profile, and profile names are unique within a team. Give it an externalId to key it on your own customer id. See Build a platform.

profileId

The _id of a profile, and the customer filter across the API: pass it to the connect flow, account listing, analytics and inbox endpoints to scope a request to one profile. Compare accountId.

Queue

Recurring posting slots defined per profile. Create a post with queuedFromProfile and no scheduledFor, and it lands on the profile's next free slot. See Queue scheduling.

scheduledFor

The field on POST /v1/posts that sets the scheduled time, read in the timezone you send with it. Omit it and set publishNow: true to publish now, or omit both to save a draft. See Timezones.

Scoped API key

An API key restricted to specific profiles (scope: "profiles" plus profileIds), optionally read-only (permission: "read"). It isolates customers; it does not raise rate limits. See scoped keys.

Secondary selection

The extra step some platforms need after OAuth: picking which Facebook Page, LinkedIn organization, Pinterest board, Google Business Profile location or Snapchat public profile to connect. See connecting accounts.

Segment (SMS)

The SMS billing unit: one 160-character GSM-7 message part (153 each when a message spans parts; 70/67 for emoji and non-Latin scripts via UCS-2). Rates are per segment, per destination; see SMS rates.

Sequence

A linear drip campaign: a series of messages sent to enrolled contacts with a delay between steps, created with POST /v1/sequences and started with POST /v1/sequences/{sequenceId}/activate. Enrol contacts with POST /v1/sequences/{sequenceId}/enroll; a reply or an unsubscribe exits them. Compare workflow.

Team

The owner plus every invited member. A team owns the API keys and the billing, and Zernio computes rate limits and the connected-account count that drives billing per team. A team contains profiles, which contain accounts.

Usage-based billing

How Zernio charges: every account includes every feature, and you pay per connected account per day, with the first 2 accounts free. Messages meter after 10,000 a month and managed ads after 500; see Pricing.

WABA (WhatsApp Business Account)

Your business's account with Meta, which a Zernio number connects to. Meta bills template delivery and its per-minute calling fee to the WABA's payment method directly, never through Zernio. See WhatsApp rates.

Webhook endpoint

An HTTPS URL you register on the webhooks page (up to 50 per team) that receives events. Zernio signs every delivery with X-Zernio-Signature when the endpoint has a secret. See the webhooks overview.

Workflow

A branching conversation automation: an event that matches the workflow's trigger (a DM, a ref link or ad click, a comment, a story mention, a reaction, a WhatsApp status or an API call) walks a graph of nodes (send message, wait for reply, condition, delay, webhook, handoff). Created with POST /v1/workflows and switched on with POST /v1/workflows/{workflowId}/activate; unlike a sequence it is event-driven rather than time-based. See Workflows.

X

The platform with value twitter. X bills every API call, so connecting an X account needs a card on file; see the platform page and X API pricing.